Not certain where to start but…my AC controls and radio rebooted while I was driving like the power blipped. Additionally, twice I noticed that when I started my car after it was parked overnight, it seemed to have lost power at some point. The symptom was that when I went to start it, the AC cycled like when the battery is disconnected. No fuses are going out, and I am not sure where to start looking or what potentially would cause this to affect the radio and AC.

Background: 2008 H3 Alpha, original owner. Recent changes: new Optima battery and alternator last summer, recently (2 months ago) replaced OEM radio with BOSS app radio. Disconnected all OnStar wiring to the module and same for Sirius module.

 

My alternator is 14yrs old, and still going strong. Do you know how to search this forum? Tons of information to be found for any issue that you may have. Look at the posts below yours from today.

 

could be a bad body ground.

 

Let's try the Free stuff first.
Check ALL battery connections for corrosion inside the wire.
Try to remove and twist the battery terminals (positive & negative) without using a tool to loosen them. The OEM terminals are not very good.
If you can twist or remove them without a tool replace them with military style terminals (positive and negative are different sizes) or some car stereo style.
Check the ground from the battery to the engine block.
Also, Optima batteries can have a dead cell just like any other battery and test just fine until there is a load on them.

 

Good info, thank you all! I will replace the battery terms, and check ground to start. I did notice, when I swapped the battery, The OEM terminals were not as tight as I wanted.

@hummerz will search the forum, and yes on the Sunroof, but no H2O in either side of the floor pans/carpet. I had the sunroof drain tube bug caps drilled out the first time they clogged and flooded my cabin.

 

hummerz grabbed my broken record statement...

The first mod to do to every H3/H3t is to hack of those POS OEM Battery Terminal Connectors and replace with a quality aftermarket set!

I won't use optima batteries any more. Years back I put a Red Top in my 70 Olds 442, before that summer season was over it developed a slow leak and wreaked havoc on my 40+ year old battery tray and bottom of the inner fender by the time I spotted it. Leading to a bunch of work to take it apart, clean, refinish and reassemble along with many choice words while talking to myself. Overpriced junk IMHO.

The auto parts seller replaced it and I immediately resold that to a friend.

 

Sorry to piggyback on the above question, but where is the engine block ground located. I searched for it yesterday but i just couldn't seem to find it easily. Battery ground seems fairly straightforward.

Alternator and its connection is right in your face thankfully.

 

Ground Locations

 

i bet this was in a thread somewhere too... i did search though i swear haha.

this helps with replacing those god awful terminals

 

Fuel and electrical problems can be the most mysterious to solve.

Some good advise given. Check the usual suspected areas first. Its all here on search button. Good Battery good grounds good connections.